The Continental O-170 engine is the collective military designation for a family of small aircraft engines, known under the company designation of A50, A65, A75 and A80. The line was designed and built by Continental Motors commencing in the 1940s. It was employed as the powerplant for civil and military light aircraft.Christy (1983) The horizontally opposed, four-cylinder engines in this family are all identical in appearance, bore, stroke, dry weight, and piston displacement. All feature a bottom-mounted

updraft carburetor An updraft carburetor is a type of carburetor (a component of engines that mixes air and fuel together) in which the air enters at the bottom and exits at the top to go to the engine. An updraft carburetor was the first type of carburetor in comm ...

fuel delivery system. The higher power variants differ only in compression ratio and maximum allowable rpm, plus minor modifications. The lower power versions are fully convertible to the higher rated versions.

Design and development

In all models of this family of engines the cylinder heads are of

aluminum Aluminium (aluminum in American and Canadian English) is a chemical element with the symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately one third that of steel. It ha ...

alloy, screwed and shrunk onto

steel Steel is an alloy made up of iron with added carbon to improve its strength and fracture resistance compared to other forms of iron. Many other elements may be present or added. Stainless steels that are corrosion- and oxidation-resistan ...

barrels.

Spark plug A spark plug (sometimes, in British English, a sparking plug, and, colloquially, a plug) is a device for delivering electric current from an ignition system to the combustion chamber of a spark-ignition engine to ignite the compressed fuel/ai ...

inserts and intake valve seats are made from aluminum-

bronze Bronze is an alloy consisting primarily of copper, commonly with about 12–12.5% tin and often with the addition of other metals (including aluminium, manganese, nickel, or zinc) and sometimes non-metals, such as phosphorus, or metalloids suc ...

alloy, while the exhaust valve seats are steel. The engines all employ hydraulic tappets which operate in aluminum guides that are machined into the

crankcase In a piston engine, the crankcase is the housing that surrounds the crankshaft. In most modern engines, the crankcase is integrated into the engine block. Two-stroke engines typically use a crankcase-compression design, resulting in the fuel ...

. The tappets are built from four parts, a cam follower body, cup, cylinder, and piston and operate with clearances of to . The

pushrod A valvetrain or valve train is a mechanical system that controls the operation of the intake and exhaust valves in an internal combustion engine. The intake valves control the flow of air/fuel mixture (or air alone for direct-injected engines) ...

s are steel and feature pressed-in ball ends. Lubricating oil is delivered under pressure from the oil sump to the drive bearings and the crankpins through the crankshaft. The cylinder walls and pistons are spray lubricated. Normal operating oil pressure is 35 psi, with minimum idle oil pressure 10 psi.

Variants

Air Zoo December 2019 130 (Continental A-50)

;A50 :, Compression ratio 5.4:1, max rpm 1,900, fuel consumption at cruise 3.8 US gph ;A50-1: ;A50-2: ;A50-3: ;A50-4: ;A50-5: ;A50-6: ;A50-7: ;A65 :, Compression ratio 6.3:1, max rpm 2,300, fuel consumption at cruise 4.4 US gph. The exhaust valves have stellite faces. The pistons have three rings, although some early production A65s had four piston rings.Teledyne Continental Motors: ''Continental Aircraft Engine Operator's Manual'', pages 4-5. Teledyne Continental Motors, FAA Approved December 1980. Continental Form No. X30012 ;A65-1: ;A65-2: ;A65-3: ;A65-4: ;A65-5: ;A65-6: ;A65-7: ;A65-8: ;A65-8F: :A65-9: ;A65-12: ;A75 :, Compression ratio 6.3:1, max rpm 2,600, fuel consumption at cruise 4.8 US gph. The exhaust valves have stellite faces and the connecting rods have a hole drilled in the rod cap to improve lubrication. The pistons have three rings and smaller piston pins. ;A75-1: ;A75-2: ;A75-3: ;A75-4: ;A75-5: ;A75-6: ;A75-14: ;A80 :, Compression ratio 7.55:1, max rpm 2,700, fuel consumption at cruise 5.2 US gph. The connecting rods have a hole drilled in the rod cap to improve lubrication. The pistons have five rings and smaller piston pins. ;A80-1: ;A80-2: ;A80-3: ;A80-4: ;A80-5: ;A80-6: ;A80-8: ;O-170 :Military designation for the A50, A65, A75, A80 family of engines. ;O-170-1: ;O-170-3: ;O-170-5: ;O-170-7:

Applications

;A50 * Aeronca KCA * Aeronca 50C * Aeronca 50TC * Aeronca S50C * Luscombe 8 *

Piper J-3 The Piper J-3 Cub is an American light aircraft that was built between 1938 and 1947 by Piper Aircraft. The aircraft has a simple, lightweight design which gives it good low-speed handling properties and short-field performance. The Cub is Pi ...

Piper J-4 The Piper J-4 Cub Coupe is a two place side-by-side version of the Piper J-3 that was built between 1938 and 1942 by Piper Aircraft. It was Piper's first model with side-by-side seating; combined with docile low-speed handling, this made it a good ...

* Porterfield CP50 * Porterfield CP55 * Taylorcraft BC * Taylorcraft BCS ;A65 ContinentalA65

* Aeronca L-3 * Aeronca S65C * Aeronca S65CA * Aeronca 65F *

Aeronca 65CA The Aeronca Model 50 Chief was an American light plane of the late 1930s. Consumer demand for more comfort, longer range and better instrumentation resulted in its development in 1938, powered by a 50-horsepower (37-kilowatt) Continental, Frankl ...

Aeronca Champion The Aeronca Model 7 Champion, commonly known as the "Champ", or "Airknocker",Bellanca Aircraft Corp, " d: "The Champ only $4,995"" ''Flying Annual & Pilots' Guide,'' 1971 ed., pp.36–37 iff-Davis NY is a single-engine light airplane with a ...

* Airdrome Fokker D-VIII * Bearhawk LSA *

Cassutt Special The Cassutt Special is a single-seat sport and racing aircraft designed in the United States in 1951 for Formula One air races. Plans are still available for homebuilding. Designed by ex-TWA captain Tom Cassutt, it is a mid-wing cantilever mo ...

* Christavia Mk I *

Circa Reproductions Nieuport The Circa Reproductions Nieuports are a family of Canadian 7/8 scale World War I sesquiplane aircraft replicas designed by Graham Lee of Lamont, Alberta for amateur construction from plans sold by Lee's company Circa Reproductions. Leading E ...

Coupé-Aviation JC-01 The Coupé-Aviation JC-01 is the first of a series of very similar designs of two seat, single engine sports aircraft, amateur built from plans in France from 1976. These provided a range of engine sizes and undercarriage layouts, but total pr ...

* Davis DA-2 * Davis DA-5 * Ercoupe 415C * E & P Special *

Falconar F11 Sporty The Falconar F11 Sporty is a Canadian amateur-built aircraft, that was designed by Chris Falconar and produced by Falconar Avia. Falconar supplied it as a kit or as plans for amateur construction. Today both the F11A and E models are available ...

Fisher Celebrity The Fisher Celebrity is a Canadian two-seat, conventional landing gear, single engined, biplane kit aircraft designed for construction by amateur builders. Fisher Flying Products was originally based in Edgeley, North Dakota, United States but ...

* Fisher Dakota Hawk * Helmy AerogyptJackson (1974) * Henderson Little Bear * Interstate SIA Cadet * Jameson RJJ-1 Gipsy Hawk * Jodel D.112 * Luscombe 8A * Luscombe 10 *

Piper J-4A The Piper J-4 Cub Coupe is a two place side-by-side version of the Piper J-3 that was built between 1938 and 1942 by Piper Aircraft. It was Piper's first model with side-by-side seating; combined with docile low-speed handling, this made it a good ...

* Porterfield CP65 * Rearwin Skyranger 165 * Smith MiniplanePlane & Pilot: ''1978 Aircraft Directory'', page 153. Werner & Werner, 1978. * Stolp SA-900 V-Star * Taylorcraft BCS * Taylorcraft BCS12 * Taylorcraft 65 *

Tayorcraft BC The Taylorcraft B is an American light, single-engine, high-wing general aviation monoplane, with two seats in side-by-side configuration, that was built by the Taylorcraft Aviation Corporation of Alliance, Ohio.The Pittsburgh PressMove Stat ...

* Taylorcraft BC1265 *

Taylorcraft BCT The Taylorcraft B is an American light, single-engine, high-wing general aviation monoplane, with two seats in side-by-side configuration, that was built by the Taylorcraft Aviation Corporation of Alliance, Ohio.The Pittsburgh PressMove Stat ...

* Taylorcraft L-2 *

Taylorcraft Tandem The Taylorcraft L-2 Grasshopper is an American observation and liaison aircraft built by Taylorcraft for the United States Army Air Forces in World War II. Design and development In 1941 the United States Army Air Forces ordered four Taylorc ...

* Turner T-40 *

Warner Revolution I The Warner Revolution I, also marketed as the Spacewalker I, is an American homebuilt aircraft that was designed and produced by Warner Aerocraft of Seminole, Florida. When it was available the aircraft was supplied as a kit or in the form of ...

* Wolf W-11 Boredom Fighter ;A75 * Bearhawk LSA *

Culver LCA The Culver Cadet is an American two-seat light monoplane aircraft, also as a radio-controlled drone, produced by the Culver Aircraft Company. Design and development The aircraft designer Al Mooney developed an improved version of the Culver Dart ...

* Jodel D.121 * Luscombe 8C * Luscombe 8D * Piper J-4E *

Piper J-5 The Piper J-5 Cub Cruiser was a larger, more powerful version of the basic Piper J-3 Cub. It was designed just two years after the J-3 Cub, and differed by having a wider fuselage with the pilot sitting in the front seat and two passengers sittin ...

* Piper J-5A * Porterfield 75C * Rearwin Skyranger 175 * Stinson Model 105 (HW-75) ;A80 *

Harris Geodetic LW 108 The Harris Geodetic LW 108 is an American homebuilt aircraft that was designed by J. Warren Harris of Vernal, Utah and made available in the form of plans for amateur construction.Plane and Pilot: ''1978 Aircraft Directory'', page 143. Werner ...

* Piper J-5A-80 * Shirlen Big Cootie * Stinson Model 105 (HW-80) * Stinson Model 10 *

Vought V-173 The Vought V-173 "Flying Pancake" was an American experimental test aircraft built as part of the Vought XF5U program during World War II. Both the V-173 and the XF5U featured an unorthodox "all-wing" design consisting of flat, somewhat disk-sh ...

Specifications (O-170-3 or A-65-8)

Notes

References